The present invention relates to a method for producing a polymer pellet in which in storing, transporting or feeding to a processing apparatus, the obtained pellets containing adhesive polymer do not easily mutually adhere, and handling thereof is excellent. The invention also relates to an apparatus used for this method.
It is known that an adhesive polymer is coated with a non-adhesive polymer, and then the coated polymer is cut to produce polymer pellets which are less adhesive.
For example, a polymer pellet having a core-sheath structure is known, which is obtained by cutting a strand of core-sheath structure in which a thermoplastic elastomer or amorphous polyolefin as a core is covered with a crystalline polyolefin as a sheath (Japanese published patent application (kokai) No. JP 7-171828 A).
There is also known a method of laminating a thermoplastic polymer film on both surfaces of a sheet of adhesive rubber, and cutting this to give a pallet (Japanese published patent application No. JP 2000-52336 A).
However, in pellets obtained by cutting with a strand cutter or pelletizer, disclosed in these technologies, an adhesive polymer, such as thermoplastic elastomer, amorphous polyolefin or rubber, is exposed on its cut surface, and the obtained pellets are not completely adhesive with each other. JP 2000-52336 A discloses a method of cutting with a cutter knife. However, productivity thereof is low, and therefore, this method is not preferable.